EP0153899A2 - Reifenlauffläche mit veränderlicher Rillentiefe - Google Patents

Reifenlauffläche mit veränderlicher Rillentiefe Download PDF

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Publication number
EP0153899A2
EP0153899A2 EP85630014A EP85630014A EP0153899A2 EP 0153899 A2 EP0153899 A2 EP 0153899A2 EP 85630014 A EP85630014 A EP 85630014A EP 85630014 A EP85630014 A EP 85630014A EP 0153899 A2 EP0153899 A2 EP 0153899A2
Authority
EP
European Patent Office
Prior art keywords
groove
distance
tire
tire according
vertex
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
EP85630014A
Other languages
English (en)
French (fr)
Other versions
EP0153899A3 (en
EP0153899B1 (de
Inventor
René Goergen
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Goodyear Tire and Rubber Co
Original Assignee
Goodyear Tire and Rubber Co
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Goodyear Tire and Rubber Co filed Critical Goodyear Tire and Rubber Co
Publication of EP0153899A2 publication Critical patent/EP0153899A2/de
Publication of EP0153899A3 publication Critical patent/EP0153899A3/en
Application granted granted Critical
Publication of EP0153899B1 publication Critical patent/EP0153899B1/de
Expired legal-status Critical Current

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Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60C—VEHICLE TYRES; TYRE INFLATION; TYRE CHANGING; CONNECTING VALVES TO INFLATABLE ELASTIC BODIES IN GENERAL; DEVICES OR ARRANGEMENTS RELATED TO TYRES
    • B60C11/00—Tyre tread bands; Tread patterns; Anti-skid inserts
    • B60C11/03—Tread patterns
    • B60C11/04—Tread patterns in which the raised area of the pattern consists only of continuous circumferential ribs, e.g. zig-zag
    • B60C11/042—Tread patterns in which the raised area of the pattern consists only of continuous circumferential ribs, e.g. zig-zag further characterised by the groove cross-section
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60C—VEHICLE TYRES; TYRE INFLATION; TYRE CHANGING; CONNECTING VALVES TO INFLATABLE ELASTIC BODIES IN GENERAL; DEVICES OR ARRANGEMENTS RELATED TO TYRES
    • B60C11/00—Tyre tread bands; Tread patterns; Anti-skid inserts
    • B60C11/03—Tread patterns
    • B60C11/0306—Patterns comprising block rows or discontinuous ribs
    • B60C11/0309—Patterns comprising block rows or discontinuous ribs further characterised by the groove cross-section
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60C—VEHICLE TYRES; TYRE INFLATION; TYRE CHANGING; CONNECTING VALVES TO INFLATABLE ELASTIC BODIES IN GENERAL; DEVICES OR ARRANGEMENTS RELATED TO TYRES
    • B60C11/00—Tyre tread bands; Tread patterns; Anti-skid inserts
    • B60C11/03—Tread patterns
    • B60C11/13—Tread patterns characterised by the groove cross-section, e.g. for buttressing or preventing stone-trapping
    • B60C11/1307—Tread patterns characterised by the groove cross-section, e.g. for buttressing or preventing stone-trapping with special features of the groove walls
    • B60C11/1315—Tread patterns characterised by the groove cross-section, e.g. for buttressing or preventing stone-trapping with special features of the groove walls having variable inclination angles, e.g. warped groove walls
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60C—VEHICLE TYRES; TYRE INFLATION; TYRE CHANGING; CONNECTING VALVES TO INFLATABLE ELASTIC BODIES IN GENERAL; DEVICES OR ARRANGEMENTS RELATED TO TYRES
    • B60C11/00—Tyre tread bands; Tread patterns; Anti-skid inserts
    • B60C11/03—Tread patterns
    • B60C11/13—Tread patterns characterised by the groove cross-section, e.g. for buttressing or preventing stone-trapping
    • B60C11/1307—Tread patterns characterised by the groove cross-section, e.g. for buttressing or preventing stone-trapping with special features of the groove walls
    • B60C11/1323—Tread patterns characterised by the groove cross-section, e.g. for buttressing or preventing stone-trapping with special features of the groove walls asymmetric

Definitions

  • This invention relates to tire treads and more particularly to tire treads having a plurality of zig-zag ribs separated by parallel zig-zag grooves with varying depths along their lengths.
  • Tires especially truck tires with circumferential zig-zag ribs, have been observed to be susceptible to a type of uneven wear generally referred to as "river wear".
  • This type of wear which can be observed on trucks running on highways, is characterized in that the protruding portions of the ribs wear faster than the recessed portions of the ribs. It is generally believed that this type of wear is caused by excess stresses localized at the protruding portions of the ribs. It is furthermore believed that by making the rib peaks more flexible as compared to the rib corners, the uneven wear can be reduced to a great extent.
  • This invention provides the desired localized flexibility by varying the depth of the zig-zag grooves in the circumferential direction of the tire such that they are deepest at the vertices of the projecting angles of the ribs and shallowest at the vertices of the reentrant angles of the ribs.
  • a tire having a tread with a pair of circumferentially extending ribs separated by a circumferentially extending zig-zag groove, said zig-zag groove having a pair of walls, respectively associated with said pair of ribs, and a base, each wall connecting the base of the groove with the ground-engaging surface of the respective rib, each rib having a series of alternately projecting and reentrant angles with the vertices of said angles located at points where the respective groove walls make changes in direction with respect to the axis of rotation of said tire, characterized in that throughout the useful life of the tire the base of said groove comprises a surface which is disposed at a radially measured distance from the ground-engaging surfaces of the ribs which varies in the circumferential direction of the tire and which distance is at a maximum at the vertex of each of said projecting angles and at a minimum at the vertex of each of said reentrant angles.
  • Fig. 1 shows a portion of a tread 10 of a pneumatic tire which is generally used on medium and heavy trucks.
  • the tread comprises a plurality of circumferentially extending ribs 11 which are separated by circumferentially extending zig-zag grooves 12.
  • zig-zag refers to an undulating or sinusoidal pattern as well as to the conventional pattern of a series of adjacent straight segments alternating in direction with respect to the axis of rotation of the tire.
  • Each rib 11 that has a ground-engaging surface with an axial edge defining a zig-zag groove 12 has a series of alternating projecting angles 13 and reentrant angles 14.
  • the vertex of an angle means a point where a respective groove wall makes a change in direction with respect to the axis of rotation of the tire.
  • a zig-zag groove in accordance with this embodiment of the invention has a pair of groove walls 15, 16 connecting the groove base 17 with a ground-engaging surface 18 of the rib or ribs 11 that define the groove.
  • the distance from the surface of the groove base to the ground-engaging surface of the tread means the distance such as measured in the radial direction, i.e. perpendicular to the axis of rotation of the tire, from a particular point on the base or floor of the groove to the ground-engaging surface of the tread. This distance is referred to as the "depth" of the groove.
  • the radially measured distance from the surface of the groove base to the ground-engaging surface of the tread may either vary continuously or step-wise; that is to say, the groove base may be either a continuously warped surface or a surface that is both stepped in the circumferential direction of the tire and tapered in the axial direction. It is preferable that the grooves have a greater width at the ground-engaging surfaces of the tread than at the groove base, and that the angle each groove wall 15, 16 forms with respect to a line perpendicular to the ground-engaging surface of the tread remains constant around the circumference of the tire.
  • Figs. 2, 3, and 4 which are cross sectional views along the lines 2-2, 3-3, and 4-4 respectively of Fig. 1 of a groove 12, on a larger scale than in Fig. 1, the continuously varying depth of the groove can be clearly seen.
  • the embodiment of the invention wherein the depth of the groove varies stepwise is not illustrated in the drawing.
  • Fig. 3 is a cross section of a groove 12 at a location midway between the ends of one leg of the zig-zag groove.
  • the groove base 17 in Fig. 3 has a depth c that is preferably the nominal depth, or non-skid depth of the groove.
  • the groove in Fig. 2 is a cross-section of the same groove located at the vertices of both a projecting angle 13 of a first rib and the associated re-entrant angle 14 of a second rib, with the two ribs defining the edges of the groove.
  • the groove in Fig. 2 has a maximum depth a at the vertex of the projecting angle of the first rib and a minimum depth b at the vertex of the re-entrant angle of the second rib.
  • the maximum depth a of the groove should be no more than about 5 millimeters greater than the nominal depth c of the groove and the minimum depth b of the groove should be no more than about 5 millimeters less than the nominal depth c of the groove.
  • the maximum depth of the groove should be no more than 10 millimeters greater than its minimum depth, and preferably the maximum and minimum depths should not vary by more than 3.5 millimeters from the nominal depth. For example, if the nominal depth of the groove is 13 millimeters, then the depth of the groove at the vertex of each projecting angle should be no more than 18 millimeters, and the depth of the groove at the vertex of each re-entrant angle should be no less than 8 millimeters.
  • Fig. 4 is a cross-section of the same groove shown in Figs. 2 and 3 taken along line 4-4 of Fig. 1 such that the rib that was presenting the vertex of a projecting angle in Fig. 2 is now presenting the vertex 14 of a reentrant angle and the rib that was presenting the vertex of a reentrant angle in Fig. 2 is now presenting the vertex 13 of a projecting angle.
  • the depth of the groove is once again a maximum at the vertex of the projecting angle and a minimum at the vertex of the re-entrant angle due to the continuously varying depth of the warped surface of the groove base 17.
  • Fig. 5 shows a portion of a tread 20 of a tire that is similar to that illustrated in Fig. 1. While functioning along the same lines as the tread shown in Fig. 1, the grooves 21 have groove bases that comprise two surfaces 22, 23 with each of the surfaces being adjacent to one of the groove walls 24, 25 and being connected to one another by radially extending connecting surfaces 28. Each of the groove base surfaces 22, 23 has a varying depth which is at a maximum at the vertex of each of the respective projecting angles 26 of a rib 29, and at a minimum at the vertex of each of the respective re-entrant angles 27 of a rib 29.
  • each surface of the groove base may vary either continuously or step-wise; that is to say, each of the groove base surfaces may be either continuously radially inclined and extending in the circumferential direction or radially stepped and extending in the circumferential direction.
  • the stepped embodiment is not shown in the drawing.
  • Figs. 6, 7, and 8 which are radial cross-sectional views of a zig-zag groove 21 along the lines 6-6, 7-7, and 8-8, respectively, of Fig. 5, the varying depth of the groove according to this embodiment can be clearly pointed out.
  • the other basic features of the grooves shown in and described with respect to Figs. 1 through 4 also apply to this embodiment with the exception of the multi-surface groove base.
  • Fig. 7 it can be seen that midway along the length of one leg of the zig-zag groove, both of the groove base surfaces 22 and 23 are located at the same nominal depth c.
  • each groove base surface has a maximum depth a
  • each groove base surface has a minimum depth b.
  • the maximum depth of the groove should be no more than 10 millimeters greater than the minimum depth. It is preferred that the maximum and minimum depths do not vary by more than 3.5 millimeters from the nominal depth.
  • FIG. 9 shows a portion of a tread 30 of a tire that is similar to that illustrated in Figs. 1. and 5.
  • a tire having a tread made in accordance with either of these embodiment of the invention is characterized in that the groove base 37 is located at a first depth and a series of depressions 39 in the groove base that have a second depth that is greater than the first depth, with one of the depressions being located at the vertex of each of the projecting angles 33 of a rib 31 bordered by the zig-zag groove. It is preferable that the grooves have a greater axial width at the ground-engaging surfaces of the ribs than at the groove base, and that the angle that each groove wall 35, 36 forms with respect to a line perpendicular to the ground-engaging surface of the respective rib remains constant around the circumference of the tire.
  • Figs. 10, 11 and 12 are radial cross-sectional views of a groove 32 on a larger scale than in Fig. 9 along the lines A-A, B-B, and C-C, respectively, of Fig. 9, the relative depths of the groove base and the depressions can be clearly pointed out.
  • Fig. 10 is a cross-section of a groove 32 at a location that does not intersect one of the depressions in the groove base and the groove base is located at a first depth that is constant across the axial width of the groove base.
  • Fig. 11 is a cross-section of the same groove 32 at a location that does intersect one of the depressions in the groove base, but this location is not precisely at the vertex of a projecting angle of a rib, and it can be seen that the depression has a second depth that is greater that the first depth of the groove base.
  • Fig. 12 is a cross-section of the same groove 32 at a location adjacent to the vertex of a projecting angle of an adjacent rib. It can be seen in Fig. 12 that the depression has the same depth as in Fig. 11, and that the projecting angle of the rib adjacent to the depression should be more flexible than the re-entrant angle of the other rib adjacent to the groove base because of the greater length of the groove wall at the depression.
  • the depressions should have a maximum depth that is no more than 5 millimeters greater than the depth of the groove base, and most preferably no more than about 3.5 millimeters greater.
  • the depressions have an axial width at the vertices of the projecting angles, as illustrated at 40, that is no more than one-half of the axial width of the groove base at the vertices of the projecting angles. Furthermore, as illustrated at 41 in Fig. 9, it is preferable that the depressions have a length, as measured along the adjacent groove wall, that is no more than one-half of the distance measured along said groove wall between the vertex of a projecting angle and the vertex of one of its next circumferentially adjacent re-entrant angles.
  • Figs. 13 and 14 another embodiment of the invention will be illustrated wherein the depressions have a depth that varies over the area of the depressions and is greatest adjacent to the vertex of a projecting angle of a rib.
  • the groove will have a cross-section like that shown in Fig. 10 unless it is in a location that intersects a depression.
  • Fig. 13 is a cross-section of a groove taken along B-B of Fig. 9 that intersects a depression and is not adjacent to the vertex of a projecting angle. It is clear in Fig. 13 that the groove base 37 is located at a first depth a, and that the depression 28 has a second depth b that is greater than the depth a of the groove base.
  • the maximum depth c of the depression should be no more than 5 millimeters greater than the nominal depth a of the groove, and most preferably no more than about 3.5 millimeters greater.
  • the depressions 39 illustrated in Fig. 9 have a shape, as viewed looking radially inwardly towards the tread, with the sides of the depressions substantially parallel to the respective groove walls.
  • the depression 42 in the groove 43 has legs that are each triangular as viewed looking radially inwardly towards the tread.
  • the depression 44 in the groove 45 has legs that are quadrilateral as viewed looking radially inwardly towards the tread.
  • the depression 46 in the groove 47 has a crescent-like shape as viewed looking radially inwardly towards the tread.
  • the depression 48 in the groove 49 has a shape that is crescent-like, with legs extending along the groove wall.
  • the depression may have any shape consistent with the limitations set forth herein, without deviating from the spirit of the invention.

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Tires In General (AREA)
EP19850630014 1984-02-27 1985-02-26 Reifenlauffläche mit veränderlicher Rillentiefe Expired EP0153899B1 (de)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US58419184A 1984-02-27 1984-02-27
US584191 1984-02-27

Publications (3)

Publication Number Publication Date
EP0153899A2 true EP0153899A2 (de) 1985-09-04
EP0153899A3 EP0153899A3 (en) 1987-01-21
EP0153899B1 EP0153899B1 (de) 1988-10-26

Family

ID=24336275

Family Applications (1)

Application Number Title Priority Date Filing Date
EP19850630014 Expired EP0153899B1 (de) 1984-02-27 1985-02-26 Reifenlauffläche mit veränderlicher Rillentiefe

Country Status (3)

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EP (1) EP0153899B1 (de)
CA (1) CA1237055A (de)
DE (1) DE3565804D1 (de)

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0216566A3 (en) * 1985-09-10 1988-09-14 Sumitomo Rubber Industries Limited Pneumatic radial tyre
GB2231538A (en) * 1989-05-15 1990-11-21 Bridgestone Corp Pneumatic tire with directional tread
EP0411773A1 (de) * 1989-08-02 1991-02-06 Bridgestone Corporation Luftreifen mit erhöhter Wasserableitung
GB2326386A (en) * 1997-06-19 1998-12-23 Sumitomo Rubber Ind Tyre treads
WO2011072896A1 (de) * 2009-12-17 2011-06-23 Continental Reifen Deutschland Gmbh Fahrzeugluftreifen
CN107000499A (zh) * 2014-11-24 2017-08-01 大陆轮胎德国有限公司 车辆充气轮胎
EP3978274A1 (de) 2020-10-01 2022-04-06 Continental Reifen Deutschland GmbH Nutzfahrzeugreifen

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE2029844A1 (de) * 1969-06-19 1970-12-23 Michelin & Cie. (Compagnie Generale des Etablissements Michelin), Clermont-Ferrand (Frankreich) Luftreifen
FR2338814A1 (fr) * 1976-01-26 1977-08-19 Pirelli Pneumatique a caracteristiques de comportement au guidage et de tenue sur route partiquement constantes lorsque l'usure augmente
US4271885A (en) * 1977-04-26 1981-06-09 Bridgestone Tire Co., Ltd. Heavy duty pneumatic radial tire exhibiting less railway wear
EP0069464A2 (de) * 1981-06-12 1983-01-12 Dunlop Limited Luftreifen Lauffläche

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE2029844A1 (de) * 1969-06-19 1970-12-23 Michelin & Cie. (Compagnie Generale des Etablissements Michelin), Clermont-Ferrand (Frankreich) Luftreifen
FR2338814A1 (fr) * 1976-01-26 1977-08-19 Pirelli Pneumatique a caracteristiques de comportement au guidage et de tenue sur route partiquement constantes lorsque l'usure augmente
US4271885A (en) * 1977-04-26 1981-06-09 Bridgestone Tire Co., Ltd. Heavy duty pneumatic radial tire exhibiting less railway wear
EP0069464A2 (de) * 1981-06-12 1983-01-12 Dunlop Limited Luftreifen Lauffläche

Cited By (14)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0216566A3 (en) * 1985-09-10 1988-09-14 Sumitomo Rubber Industries Limited Pneumatic radial tyre
GB2231538A (en) * 1989-05-15 1990-11-21 Bridgestone Corp Pneumatic tire with directional tread
US5044414A (en) * 1989-05-15 1991-09-03 Bridgestone Corporation Pneumatic tire with directional tread
GB2231538B (en) * 1989-05-15 1993-03-24 Bridgestone Corp Pneumatic tire with directional tread
EP0411773A1 (de) * 1989-08-02 1991-02-06 Bridgestone Corporation Luftreifen mit erhöhter Wasserableitung
GB2326386B (en) * 1997-06-19 2001-11-21 Sumitomo Rubber Ind Vehicle tyre tread groove with radially inward extension
GB2326386A (en) * 1997-06-19 1998-12-23 Sumitomo Rubber Ind Tyre treads
WO2011072896A1 (de) * 2009-12-17 2011-06-23 Continental Reifen Deutschland Gmbh Fahrzeugluftreifen
CN102811870A (zh) * 2009-12-17 2012-12-05 大陆轮胎德国有限公司 车辆充气轮胎
CN102811870B (zh) * 2009-12-17 2015-05-27 大陆轮胎德国有限公司 车辆充气轮胎
CN107000499A (zh) * 2014-11-24 2017-08-01 大陆轮胎德国有限公司 车辆充气轮胎
CN107000499B (zh) * 2014-11-24 2020-04-07 大陆轮胎德国有限公司 车辆充气轮胎
EP3978274A1 (de) 2020-10-01 2022-04-06 Continental Reifen Deutschland GmbH Nutzfahrzeugreifen
DE102020212455A1 (de) 2020-10-01 2022-04-07 Continental Reifen Deutschland Gmbh Nutzfahrzeugreifen

Also Published As

Publication number Publication date
CA1237055A (en) 1988-05-24
EP0153899A3 (en) 1987-01-21
EP0153899B1 (de) 1988-10-26
DE3565804D1 (en) 1988-12-01

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